Heart Failure: Nutritional Considerations

Diet therapy for congestive heart failure chiefly involves restriction of excess sodium and fluid, which can overburden an already reduced ability to handle plasma volume due to weakening of the heart muscle. Because the condition is usually the result of long-term cardiovascular disease, treatment should also include diet therapy for CHD (see Coronary Heart Disease), along with adequate calories to prevent the excessive weight loss that may accompany this condition. The primary nutritional considerations are as follows:

Sodium reduction. A higher intake of dietary sodium is a strong and independent risk factor for heart failure in overweight persons.⁵ In patients with heart failure, sodium restriction is an important part of treatment and may reduce the need for diuretic therapy.⁶ Restriction of sodium to 2000 to 2400 mg per day, along with fluid restriction to 1.5 liters daily, improves functional class and reduces edema.⁷ The most commonly recommended limit is 2000 mg of sodium daily.⁸ Moderation in sodium intake is also important for the control and treatment of hypertension (see Hypertension), which increases risk for heart failure.⁹

Maintaining magnesium adequacy. About 30% of heart failure patients have magnesium deficiency, which can cause a positive sodium balance and negative potassium balance and is associated with a poorer prognosis.10

Thiamine supplements for patients treated with diuretics. Evidence of vitamin B1 deficiency has been found in 57% to 98% of patients treated with diuretics; the risk increases in a dose-related manner.11 Supplementation with high-dose thiamine (200 mg/day) improves both biochemical indicators of deficiency and left ventricular function.12,13

Dietary supplements as adjunctive treatments. A meta-analysis of controlled clinical trials with coenzyme Q10 found significant improvements in stroke volume, cardiac output, cardiac index, and end-diastolic volume in patients with heart failure, regardless of etiology (eg, idiopathic, dilated, ischemia, hypertension, valvular heart disease, and congenital heart disease).14 Amounts typically used range from 150 mg to 300 mg per day as a supplement to conventional treatment.

Other supplements, including L-carnitine, taurine, and the herb crataegus oxycantha L, are under investigation for possible roles in heart failure treatment.15-23 None of these is yet established as safe and effective.

Orders

Diet: Sodium less than 2 grams daily. When heart failure is the result of heart disease, a cardiovascular-specific diet should be ordered (see Coronary Heart Disease).

Fluid restriction as appropriate.

Nutrition consultation to help the patient adjust to the above diet.

Exercise physiologist, physical therapist, and occupational therapist consultations to prescribe exercise regimen and provide appropriate support for activities of daily living.

What to Tell the Family

Heart failure is a progressive disease. However, patients may be able to prolong survival, improve chronic symptoms, avoid repeated episodes of decompensation, and decrease the need for hospitalization by following a low-sodium diet, restricting fluids, and taking medications as prescribed. Exercise conditioning is also important, as it can help improve exercise tolerance and oxygen uptake. The family may need to provide physical support as the patient attempts to recondition, and help the patient comply with diet changes.